The present invention relates to clear washable bi- or multiphasic lubricant compositions, including personal lubricants, skin conditioners, shaving fluids, and methods for their manufacture and use. Such lubricant compositions are preferably silicone-containing, substantially water-soluble, clear, and generally maintain their lubricity longer than purely water-soluble lubricant, skin conditioning, and shaving compositions of the prior art lacking a silicone component. In certain embodiments the present invention includes condom products including the lubricant compositions of the present invention, and methods of making such condom products. In one particular aspect, the substantially water-soluble, clear, multi-phasic lubricant compositions of the present invention are self-warming lubricant compositions, for example, self-warming personal lubricant compositions, condom products including condoms lubricated with warming lubricant compositions, and method of making such condom products.
Lubrication can be defined as the separation of moving surfaces to prevent them from coming into direct contact with each other (or to reduce the amount of such friction); this tends to prevent or lessen wear and irritation between the surfaces.
Personal lubricants, for example, in the form of water-soluble pourable liquids, water-soluble pourable low viscosity thixotropic gels, water-soluble jellies and the like, are known and are useful for providing lubricity to various parts of the human body, for example, to mucous membranes, such as the oral, rectal, vaginal and other mucosa. For example, see Ahmad et al U.S. Pat. No. 5,885,591, the disclosure of which is incorporated in its entirety herein by reference. Certain such lubricants have been proposed which may generate heat or warming when placed in contact with the human body. See also, Harrison, J., U.S. patent application Ser. No. 11/089,953, published as U.S. Patent Publication 2006/0217272 A1.
Additional personal lubricants have been discussed in e.g., Ahmad et al., U.S. Pat. No. 6,139,848, Ahmad et al., U.S. Pat. No. 7,005,408, Ahmad et al., U.S. Pat. No. 7,285,517, and Harrison, U.S. Pat. No. 7,405,186. These are water-soluble lubricants lacking a silicone component. Some water-soluble lubricants may be tacky and lack a sufficiently high degree of lubricity.
On the other hand, silicone lubricants offer superior lubrication, but generally stain fabrics such as cotton, polyester or satin, can feel greasy and can be difficult to clean up. Silicone and water-soluble phases are immiscible. Therefore an emulsion is necessary to take advantage of the combination of these phases.
Generally emulsions between two immiscible substances are substantially opaque “white” creams due to the admixture of droplets of, for example, oil (such as silicone oil) and of the aqueous phase, wherein the refractive indices of the immiscible phases are different. However, opaque or translucent personal lubricants, particularly those used as sexual lubricants, may appear used, and are therefore generally considered aesthetically unpleasing and may be commercially unsuccessful because of this, despite their physical properties.
Clarification of cosmetics has generally involved using one of two possible approaches: a) the formation of microemulsions or b) matching of refractive indices. See e.g., Sun et al., J. COSMET. Sci. 56, 253-265 (July/August 2005). The formation of microemsulsions generally involves the use of high concentrations of emulsifiers to compete for limited amounts of an oil phase; this force the droplet size to be very small. When the droplet size is less than the wavelength of light, the emulsion will appear clear.
When using the technique of refractive index matching to clarify a mixture of immiscible liquids, generally the formulation is determined empirically and the methodology used in one instance is often not generally applicable, for example, to all or even most formulations. See id. In one reference, an anti-perspirant composition is made using silicone oil and an aqueous liquid. However, this reference contains no methodology, theoretic basis, or even examples of refractive indices. See Karassik et al., U.S. Pat. No. 5,925,338.
Silicone personal lubricants are described in Fevola et al., Cosmetics and Toiletries, 123:6, 59-68 (June 2008). Such personal lubricants are described as being very lubricious, but clean-up is difficult since these personal lubricants are water insoluble.
Lubrication can also be an advantageous property of shaving fluids. The greater the degree of lubrication while shaving, the lesser the tendency for the razor to irritate the skin. The increased lubricity of the present compositions, combined with their clarity or translucence can add to the aesthetic appeal and marketability of such a composition as well.
Personal lubricants, for example, in the form of pourable liquids, pourable low viscosity thixotropic gels, jellies and the like, are known and are useful for providing lubricity to various parts of the human body, for example, to mucous membranes, such as the oral, rectal, vaginal and the like mucosa. For example, see Ahmad et al U.S. Pat. No. 5,885,591, the disclosure of which is incorporated in its entirety herein by reference. Certain such lubricants have been proposed which generate heat or warming when placed in contact with the human body.
Using condoms lubricated with clear lubricants has also been proposed. Producing such lubricated condoms is somewhat challenging, particularly if the lubricant is to be applied both inside and on the outside of the condom. Conventional machinery used in condom manufacture mandates that the lubricant composition has relatively tight specifications, for example, in terms of viscosity, tackiness and stringiness, as well as providing the desired degree of lubricity.
Also lubrication in a skin conditioner, particularly skin conditioners containing silicone, can give a smooth, silky feeling to dry, chapped skin. However, a single-phase silicone skin conditioner can be difficult to wash away. Moreover, an opaque or cloudy skin conditioner is unappealing when it is being used, as it may be visible as a layer on the skin.
There continues to be a need for new substantially clear personal lubricant, skin conditioner and shaving fluid compositions having increased lubricity, a smooth, non-tacky feel, and good longevity, which can be cleaned relatively easily and which does not stain clothing, as well as for condom products including personal lubricants and methods of making such materials, for example, new lubricant compositions, condom products including clear, non-staining lubricants and methods of making such condom products.